HUMAN INFLUENZA

Influenza, commonly referred to as the flu, is an infectious disease caused by RNA viruses of the family Orthomyxoviridae (the influenza viruses), that affects birds and mammals. The most common symptoms of the disease are chills, fever, sore throat, muscle pains, severe headache, coughing, weakness/fatigue and general discomfort. Sore throat, fever and coughs are the most frequent symptoms. In more serious cases, influenza causes pneumonia, which can be fatal, particularly for the young and the elderly.

in developed countries Vaccinations against influenza are usually given to people and also to farmed poultry. A vaccine formulated for one year may be ineffective in the following year, since the influenza virus evolves rapidly, and new strains quickly replace the older ones. Antiviral drugs can be used to treat influenza, with neuraminidase inhibitors being particularly effective.

Influenza spreads around the world in seasonal epidemics, resulting in the deaths of between 250,000 and 500,000 people every year, up to millions in some pandemic years. On average 41,400 people died each year in the  between 1979 and 2001 from influenza. In 2010 the CDC in the  changed the way it reports the 30 year estimates for deaths. Now they are reported as a range from a low of about 3,300 deaths to a high of 49,000 per year.

For both seasonal influenza and highly pathogenic avian influenza, ChemDiv has capabilities in the following: antiviral in vitro compound testing; high throughput screening; evaluation in established in vivo models; and, in vitro and in vivo vaccine development and services.

Antivirals – In Vitro Compound Testing

Influenza antiviral evaluation assay examines the effects of compounds at designated dose-response concentrations on cell viability. Madin Darby canine kidney (MDCK) cells are used in the assay to test the efficacy of the compounds in preventing the cytopathic effect (CPE) induced by influenza infection. The program features include:

  • Tamiflu, or Amantadine can be included in each assay as a positive control compounds.
  • Cell viability is determined 24, 48, and 72 hours later.
  • EC50 and EC90 values are calculated by regression analysis with semi-log curve fitting.
  • CC50 and CC90 values are determined in parallel.
  • Selectivity (therapeutic) indices (SI = TC/IC) are calculated.
  • Drug combination studies are available.
  • Other assay development is available.

High Throughput Screening

ChemDiv has over 1 million compounds available for screening against seasonal and avian influenza, and we maintain an active screening program for evaluation of new compound libraries. We offer:

  • Targeted HTS assays for neuraminidase inhibitors
  • Time of addition assays
  • Generation of resistant mutants for target identification

In Vivo Models

established animal models (such as mouse pneumonia) offer evaluation of:

  • Drug toxicology and efficacy
  • Bioavailability
  • Half-life
  • Excretory routes
  • Tissue tropism

Vaccines

In Vitro Services

  • Hemagglutination-inhibition assays
  • Neuraminidase-inhibition assays
  • Reagent production
  • Immunological assays (ELISA, Western blot)
  • Custom assays
  • Immune mechanisms
  • Microneutralization assays
  • Drug screening assays, including HTS
  • GLP studies
  • Consultation

In vivo Services

  • Pathogenesis (small/large animal models)
  • Vaccine safety/efficacy testing
  • Production of hyper-immune sera
  • Antiviral testing
  • Custom in vivo assays
  • GLP studies
  • Consultation

Virus Strains

  • A number of clinical isolates, including those currently circulating in human population
  • Mouse-adapted
  • Highly pathogenic avian influenza viruses
  • Novel or emerging influenza viruses